Submit Test

Markdown Preview

Add a Code Snippet

Snowball (100 Marks)

In late autumn evening n robots gathered in the cheerful company of friends. Each robot has a unique identifier an integer from 1 to 10^9.

At some moment, robots decided to play the game "Snowball". Below there are the rules of this game. First, all robots stand in a row. Then the first robot says his identifier. After that the second robot says the identifier of the first robot and then says his own identifier. Then the third robot says the identifier of the first robot, then says the identifier of the second robot and after that says his own. This process continues from left to right until the n-th robot says his identifier.

Your task is to determine the k-th identifier to be pronounced.

Input Format

You will be given a function with an integer and an integer array where n is the length of the integer array and k is the integer .

Constraints

1 < = n < =100000

1 < = k < = min(2 *10^9, n (n + 1) / 2)

Output Format

Return the k-th pronounced identifier (assume that the numeration starts from 1).

Sample TestCase 1

Input

2
2
1
2

Output

1

Explanation

Identifiers of robots will be pronounced in the following order: 1, 1, 2. As k = 2, the answer equals to 1.